Kelvin waves and ozone Kelvin waves in the quasi‐biennial oscillation and semiannual oscillation: A simulation by a high‐resolution chemistry‐coupled general circulation model
Kelvin waves and ozone Kelvin waves in the quasi‐biennial oscillation and semiannual oscillation: A simulation by a high‐resolution chemistry‐coupled general circulation model
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开尔文波和臭氧准两年振荡和半年振荡中的开尔文波：高分辨率化学耦合大气环流模型的模拟
DOI：
10.1029/2004jd005424
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发表时间：
2005
影响因子：
--
通讯作者：
M. Takahashi
中科院分区：
文献类型：
--
作者：
S. Watanabe;M. Takahashi
[1]利用T63L250高垂直分辨率（300 m）的化学耦合大气环流模式模拟了赤道Kelvin波和臭氧Kelvin波。该模式在赤道平流层产生了一个真实的准两年振荡（QBO）和半年振荡（SAO）。QBO的周期略长于2年，SAO表现为西风向东风的快速转换和西风的逐渐下降。对纬向波数为1的Kelvin慢波和快波的结果进行了讨论。波的结构和温度和臭氧扰动之间的相位关系与LIMS，CLAES和MLS的卫星观测结果吻合得很好。它们在平流层下部（上部）通常同相（反相），正如理论上预期的那样。在平流层上部，温度和臭氧的快Kelvin波占主导地位，因为慢Kelvin波被QBO西风有效地过滤。在这个模拟中，快速开尔文波遇到他们的临界水平在平流层上部时，纬向不对称的SAO西风增强的入侵的extratrophic行星波。除了临界水平滤波效应外，在与QBO和SAO相关的东风切变和西风切变附近，背景风对波浪特性的调制也很明显。QBO西风切变波振幅的增强与探空观测有较好的一致性。模拟结果表明，准两年期东、西风带垂直波长的增加和减小是明显的，这与线性波理论的结果是一致的。第一次证明了QBO西风切变带的下降使波周期缩短。此外，无论是慢Kelvin波还是快Kelvin波，QBO西风相的优势周期都比QBO东风相的优势周期长。
[1] Equatorial Kelvin waves and ozone Kelvin waves were simulated by a T63L250 chemistry-coupled general circulation model with a high vertical resolution (300 m). The model produces a realistic quasi-biennial oscillation (QBO) and a semiannual oscillation (SAO) in the equatorial stratosphere. The QBO has a period slightly longer than 2 years, and the SAO shows rapid reversals from westerly to easterly regimes and gradual descents of westerlies. Results for the zonal wave number 1 slow and fast Kelvin waves are discussed. Structure of the waves and phase relationships between temperature and ozone perturbations coincide well with satellite observations made by LIMS, CLAES, and MLS. They are generally in phase (antiphase) in the lower (upper) stratosphere as theoretically expected. The fast Kelvin waves in the temperature and ozone are dominant in the upper stratosphere because the slow Kelvin waves are effectively filtered by the QBO westerly. In this simulation, the fast Kelvin waves encounter their critical levels in the upper stratosphere when zonal asymmetry of the SAO westerly is enhanced by an intrusion of the extratropical planetary waves. In addition to the critical level filtering effect, modulations of wave properties by background winds are evident near easterly and westerly shears associated with the QBO and SAO. Enhancement of wave amplitude in the QBO westerly shear is well coincident with radiosonde observations. Increase/decrease of vertical wavelength in the QBO easterly/westerly is obvious in this simulation, which is consistent with the linear wave theory. Shortening of wave period due to the descending QBO westerly shear zone is demonstrated for the first time. Moreover, dominant periods during the QBO westerly phase are longer than those during the QBO easterly phase for both the slow and fast Kelvin waves.